Liquid–Liquid IInterfacial Tension in Ternary Monotectic Alloys Al–Bi–Cu and Al–Bi–Si

The liquid–liquid iInterfacial tension in the ternary monotectic alloys Al34.5−x Bi65.5Cux and (Al0.345Bi0.655)100−x Six (mass%) has been determined as a function of its Cu (Si) coIntent by a tensiometric technique. It is established that the iInterfacial tension gradually increases when either Cu or Si is added to Al–Bi alloys. The increase of σαβ can be related to the increase of the miscibility gap (both width and height) when Cu (Si) is added to the Al– Bi binary. The temperature dependences of the iInterfacial tension in binary Al34.5Bi65.5 and ternary Al23.25Bi65.5Cu11.25 and (Al0.345Bi0.655)95Si5 monotectic alloys are well described by the power function σαβ =σ0 · (1−T/TC)μ with the critical-point exponent μ=1.3.